X65MO小直径厚壁HFW海底输送管研制  

Development of X65MO Small Diameter Thick Wall HFW Offshore Linepipe

作　　者：孙磊磊[1] 屈献永[1] 郑磊[1] SUN Leilei;QU Xianyong;ZHENG Lei(Research and Development Institute,Baoshan Iron&Steel Co.,Ltd.,Shanghai 201900,China)

机构地区：[1]宝山钢铁股份有限公司中央研究院,上海201900

出　　处：《焊管》2024年第1期32-38,共7页Welded Pipe and Tube

摘　　要：针对大厚径比HFW海洋管制管过程中纵向屈强比上升的问题,研究了化学成分、冷却工艺对X65MO管线钢组织和性能的影响。结果表明,增加C元素含量或去除V元素有利于降低材料预拉伸后的纵向屈强比;试验材料在高温下卷取,其显微组织为铁素体+珠光体,轧态纵向拉伸曲线具有较长的屈服平台,预拉伸后具有最低的屈强比和最高的均匀延伸率;随着卷取温度降低,晶粒更加细小,贝氏体组织增加,预拉伸后的纵向屈强比上升幅度较大,而在相同卷取温度下,降低冷却速度有利于降低预拉伸后的纵向屈强比。根据研究结果制定了卷板工艺,试制了X65MO钢级Φ323.9 mm×14.3 mm HFW海管,管材横纵向屈强比等拉伸性能均满足规范要求。The effect of chemical composition and cooling process on the microstructure and properties of X65MO pipeline steel was studied to solve the issue of increased longitudinal yield ratio during the process of high thickness to diameter ratio HFW offshore linepipe.The results showed that increasing the content of C element or removing V element were beneficial for reducing the longitudinal yield ratio of the material after pre-tension.At high temperatures,the microstructure of test material is ferrite+pearlite,and the longitudinal tensile curve in the rolled state has a long yield plateau.After pre-tension,it has the lowest yield strength ratio and the highest uniform elongation.As the coiling temperature decreases,the grains become finer,and the bainite structure increases.The longitudinal yield strength ratio after pre-tension increases significantly.At the same coiling temperature,reducing the cooling rate is beneficial for reducing the longitudinal yield strength ratio after pre-tension.A rolling process was developed and for the developed X65MO steelΦ323.9 mm×14.3 mm HFW offshore linepipe,tensile properties,such as transverse and longitudinal flexural ratios,can meet the specification requirements.

关 键 词：HFW海底输送管 拉伸性能 屈强比 卷取温度 冷却速度 

分 类 号：TG113.25[金属学及工艺—物理冶金]